Typical damper assemblies include a damping media disposed within a cavity defined by a housing. A rotor with an O-ring extending around the rotor is pushed into the cavity so that dampened relative rotation between the housing and the rotor is achieved, However, according to the present invention, once the rotor is fully depressed into the cavity, an annular ring at the top of the rotor snaps into corresponding open slots at an open end of the housing. The snap feature of the present invention keeps the rotor securely snapped into the housing while at the same time allowing the rotor to rotate freely within the housing. When the rotor is snapped in place, an exterior torsion spring is placed over the exposed end of the rotor. One end of the spring is keyed into a corresponding anchor in the rotor and the other end of the spring is keyed into a rib defined by the housing. The spring is held in place on the rotor by a series of ramped ribs or projections molded in the exposed end of the rotor.
In operation of the damper assembly, the housing is slid into the pivot point of the lid to be damped. A keyway on one end of the housing is keyed into a corresponding slot inside the pivot point of the lid, thus integrally fixing the damper housing to the lid. The lid with damper in place is then placed into a stationary base. Flats on the exposed end of the rotor line up with mating flats in the stationary base. Pins are then pushed through the stationary base into both ends of the damper. As the damped lid is rotated downwards, the damper housing rotates with the lid while the rotor is held stationary by the base. As the lid is rotated downward, the torsion spring is loaded thus putting an upward moment on the lid. When the lid is released, the spring unwinds thus rotating the rotor through the damper media thereby creating a damped motion while forcing the lid open.
An alternative arrangement according to the present invention leaves one end of the spring unattached to the damper rotor to allow for preloading of the spring as it is assembled into the pivot point of the lid.
In prior arrangements, a separate spring has been used to open the lid whereas in the present invention, the spring is an integral part of the damper assembly.
Also, in known dampers, a cap is used to retain the rotor and O-ring relative to the housing. The present invention does not require a cap thus allowing the overall diameter of the damper assembly to be smaller and therefore fit into smaller packages.
Some prior dampers utilize an internal spring within the housing. However, such internal springs have limited rotational force capabilities. In the present invention, the spring is disposed externally which provides an increased rotational force when compared with internal spring arrangements.
The external spring according to the present invention permits preloading of the damper spring as the damper is being assembled into the mating assembly. However, the prior art internal springs cannot be preloaded before assembly.
The present invention relates to a hinge damper with an integral torsion spring. The damper includes a housing, a rotor disposed within the housing, an O-ring for retaining a damping media within the housing and a spring for urging rotation of the rotor relative to the housing.
Therefore, it is a feature of the present invention to provide a hinge damper with an integral torsion spring that overcomes the problems associated with the prior art arrangements.
Another feature of the present invention is the provision of a hinge damper with an integral torsion spring that is reliable in use and that is relatively low in cost.